CVE-2024-40958

CVE Details

Release Date:

2024-07-12

Description

In the Linux kernel, the following vulnerability has been resolved:\nnetns: Make get_net_ns() handle zero refcount net\nSyzkaller hit a warning:\nrefcount_t: addition on 0; use-after-free.\nWARNING: CPU: 3 PID: 7890 at lib/refcount.c:25 refcount_warn_saturate+0xdf/0x1d0\nModules linked in:\nCPU: 3 PID: 7890 Comm: tun Not tainted 6.10.0-rc3-00100-gcaa4f9578aba-dirty #310\nHardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014\nRIP: 0010:refcount_warn_saturate+0xdf/0x1d0\nCode: 41 49 04 31 ff 89 de e8 9f 1e cd fe 84 db 75 9c e8 76 26 cd fe c6 05 b6 41 49 04 01 90 48 c7 c7 b8 8e 25 86 e8 d2 05 b5 fe 90 <0f> 0b 90 90 e9 79 ff ff ff e8 53 26 cd fe 0f b6 1\nRSP: 0018:ffff8881067b7da0 EFLAGS: 00010286\nRAX: 0000000000000000 RBX: 0000000000000000 RCX: ffffffff811c72ac\nRDX: ffff8881026a2140 RSI: ffffffff811c72b5 RDI: 0000000000000001\nRBP: ffff8881067b7db0 R08: 0000000000000000 R09: 205b5d3730353139\nR10: 0000000000000000 R11: 205d303938375420 R12: ffff8881086500c4\nR13: ffff8881086500c4 R14: ffff8881086500b0 R15: ffff888108650040\nFS: 00007f5b2961a4c0(0000) GS:ffff88823bd00000(0000) knlGS:0000000000000000\nCS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 000055d7ed36fd18 CR3: 00000001482f6000 CR4: 00000000000006f0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n\n? show_regs+0xa3/0xc0\n? __warn+0xa5/0x1c0\n? refcount_warn_saturate+0xdf/0x1d0\n? report_bug+0x1fc/0x2d0\n? refcount_warn_saturate+0xdf/0x1d0\n? handle_bug+0xa1/0x110\n? exc_invalid_op+0x3c/0xb0\n? asm_exc_invalid_op+0x1f/0x30\n? __warn_printk+0xcc/0x140\n? __warn_printk+0xd5/0x140\n? refcount_warn_saturate+0xdf/0x1d0\nget_net_ns+0xa4/0xc0\n? __pfx_get_net_ns+0x10/0x10\nopen_related_ns+0x5a/0x130\n__tun_chr_ioctl+0x1616/0x2370\n? __sanitizer_cov_trace_switch+0x58/0xa0\n? __sanitizer_cov_trace_const_cmp2+0x1c/0x30\n? __pfx_tun_chr_ioctl+0x10/0x10\ntun_chr_ioctl+0x2f/0x40\n__x64_sys_ioctl+0x11b/0x160\nx64_sys_call+0x1211/0x20d0\ndo_syscall_64+0x9e/0x1d0\nentry_SYSCALL_64_after_hwframe+0x77/0x7f\nRIP: 0033:0x7f5b28f165d7\nCode: b3 66 90 48 8b 05 b1 48 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 48 2d 00 8\nRSP: 002b:00007ffc2b59c5e8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010\nRAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f5b28f165d7\nRDX: 0000000000000000 RSI: 00000000000054e3 RDI: 0000000000000003\nRBP: 00007ffc2b59c650 R08: 00007f5b291ed8c0 R09: 00007f5b2961a4c0\nR10: 0000000029690010 R11: 0000000000000246 R12: 0000000000400730\nR13: 00007ffc2b59cf40 R14: 0000000000000000 R15: 0000000000000000\n\nKernel panic - not syncing: kernel: panic_on_warn set ...\nThis is trigger as below:\nns0 ns1\ntun_set_iff() //dev is tun0\ntun->dev = dev\n//ip link set tun0 netns ns1\nput_net() //ref is 0\n__tun_chr_ioctl() //TUNGETDEVNETNS\nnet = dev_net(tun->dev);\nopen_related_ns(&net->ns, get_net_ns); //ns1\nget_net_ns()\nget_net() //addition on 0\nUse maybe_get_net() in get_net_ns in case net's ref is zero to fix this

See more information about CVE-2024-40958 from MITRE CVE dictionary and NIST NVD

CVSS Scoring

NOTE: The following CVSS v3.1 metrics and score provided are preliminary and subject to review.

Base Score:	5.5	CVSS Vector:	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector:	Local network	Attack Complexity:	Low
Privileges Required:	Low	User Interaction:	None
Scope:	Unchanged	Confidentiality Impact:	None
Integrity Impact:	None	Availability Impact:	High

Errata information

Platform	Errata	Release Date
Oracle Linux version 7 (kernel-uek)	ELSA-2024-12610	2024-09-10
Oracle Linux version 7 (kernel-uek-container)	ELSA-2024-12612	2024-09-11
Oracle Linux version 8 (kernel-uek)	ELSA-2024-12610	2024-09-10
Oracle Linux version 8 (kernel-uek)	ELSA-2024-12618	2024-09-12
Oracle Linux version 8 (kernel-uek-container)	ELSA-2024-12612	2024-09-11
Oracle Linux version 9 (kernel)	ELSA-2024-5363	2024-08-14
Oracle Linux version 9 (kernel-uek)	ELSA-2024-12618	2024-09-12